1. Field of the Invention
The present invention relates to an injection apparatus of a gas-liquid mixed flow which is suitable for a jet flow to be used for variously washing automobiles, wall surfaces of buildings, bottles and dishes.
The present application is based on Japanese Patent Application No. Hei. 11-210081, which is incorporated herein by reference.
2. Description of the Related Art
As this kind of injection apparatus for a gas-liquid mixed flow, there has been known a type in which the gas injection port side is provided on the outside to enclosed the injection port of a liquid injection nozzle (Unexamined Japanese Patent Publication No. Sho. 60-261566) and a type in which the liquid injection side is provided on the outside to enclosed the injection port of the gas injection nozzle (Unexamined Japanese Utility Model Publication No. Hei. 5-63658). In the invention, there has been employed a type in which the gas injection port is provided on the outside of the injection port of the liquid injection nozzle. Referring to the introduction of a pressure gas to the injection apparatus according to the related art of the former type, it has been known that a gas flow path having an annular section is formed to enclose a rectilinear liquid flow path positioned in the central portion and a gas introducing duct is connected in a vertical direction with respect to the flow path having the annular section (see the above-mentioned publication). However, the pressure gas flowing through the introducing duct changes the direction of the flow vertically during the introduction. For this reason, the resistance of the flow path is correspondingly increased, and furthermore, the introducing duct is partially connected to a part of the circumference of the gas flow path having the annular section. Consequently, it has been technically hard to distribute the flow of the pressure gas in the gas flow path uniformly with respect to the annular section. For this reason, there have been technological drawbacks.
More specifically, the outflow speed of the pressure gas is increased, the flow of the pressure gas in the gas flow path is disturbed easily so that the gas-liquid mixed flow jetted from the nozzle is also affected. Consequently, a uniform and stable mixed flow is damaged easily. Moreover, if the disturbance of the flow of the pressure gas in the gas flow path is increased, the injection state is easily unstable. Therefore, an adjustable range related to the injection state also tends to be reduced. It has also been suggested that the number of introducing ducts to be installed is increased to introduce the pressure gas from a plurality of portions on the circumference of the gas path flow. However, the structure is made complicated and the formation of the uniform flow is restricted based on a structure.
In consideration of the above-mentioned conventional technological circumstances, the present invention has been developed and has an object to avoid an increase in the resistance of a flow path in a portion for introducing a pressure gas to an injection apparatus and to improve a uniform flow for the pressure gas to be obtained more smoothly with a simple structure, thereby enhancing the uniformity and stability of the gas-liquid mixed flow jetted from the nozzle and enlarging an adjustable range related to the injection state.
In order to solve the above-mentioned problem, the invention provides an injection apparatus for a gas-liquid mixed flow which mixes and injects at least a pressure gas and a pressure liquid, a flow path for the pressure gas which is to be connected to a pressure gas feeder is formed almost rectilinearly, a liquid reservoir chamber to be connected to a pressure liquid feeder is provided in the flow path for the pressure gas, a sectional area of the flow path for the pressure fluid is gradually reduced to form an accelerating portion, an injection port for a liquid injection nozzle communicating with the liquid reservoir chamber is provided in the acceleration portion and a gas injection port is formed outside the injection port of the liquid injection nozzle. As described above, in the invention, the flow path for the pressure gas in the injection apparatus is formed almost rectilinearly. Therefore, the resistance of the flow path can be reduced. In addition, the pressure gas can flow smoothly without disturbance differently from the conventional example and the stable and good injection state having a large adjustable range can be obtained.
A gas injection port can be formed by an internal wall surface of the accelerating portion and an external wall surface of the liquid injection nozzle. Moreover, a throttling portion having a sectional area reduced may be provided on a nozzle for mixed flow injection on a downstream of the gas injection port. Furthermore, a plurality of injection ports may be provided on the liquid injection nozzle. In that case, the injection ports of the liquid injection nozzle may be arranged in a line and the gas injection port is formed flatly. Moreover, a part for forming the accelerating portion may be constituted exchangeably. Furthermore, a powder and granular material feeding portion may be provided on an upstream side of the injection port of the pressure gas. In that case, a liquid feeding portion for preventing residence of the powder and granular material may be provided on a downstream side of the powder and granular feeding portion. Moreover, a powder and granular material feeding portion ma be provided on an upstream side of the injection port of the pressure liquid. A detergent can be mixed into the pressure liquid.
Features and advantages of the invention will be evident from the following detailed description of the preferred embodiments described in conjunction with the attached drawings.